Components Characteristics of Wood Vinegar from Rice Husk Continuous Pyrolysis and Catalytic Cracking

Wood vinegar is one of the major products of biomass pyrolysis, and it contains a large number of beneficial ingredients. We investigated the components of fresh and preserved wood vinegar gained from rice husk continuous pyrolysis and catalytic cracking. The main ingredients of fresh pyrolysis wood vinegar are acids, phenols and ketones. The species of ketones are more than any other compounds, but the content of each single component is very low. After a year's preservation, the content of acids and alcohols increases, while phenols decreases. For the catalytic cracking wood vinegar, the content of acids is low, while the content of phenols and ketones is high. The content of acids, phenols and alcohols increases remarkably, and the content of ketones decreases sharply after a year. N in the wood vinegar exists in the form of amino, nitroso and cyclization. Ketol and unsaturated ketones could be generated by condensation reaction of ketones, and alcohols from the reduction reaction or addition reaction of ketones, caused the increase of alcohols and enol ketone. Phenol could be generated by dealkylation reaction of alkylphenol, and alkyl broke into small molecule alcohols and carboxylic acids, caused an increment of acids and alcohols. Acids and alcohols with longer carbon chain, which may be the by-products of some reactions or products of condensation reactions, are detected in the preserved wood vinegar.